Saltwater quality criteria were the scientific basis for the establishment of the saltwater quality standards. The assessment factor and species sensitivity distribution model were employed to deduce lead saltwater criterion. The toxicity data covered the species representing the marine biota characteristics in China. It was discovered from extensive experiments that results obtained by different methods exhibit significant difference. Based on the species sensitivity distribution model, the high saltwater quality criterion (HSWC) for lead was 275 μg/L; whereas based on the assessment factor method, low saltwater quality criterion (LSWC) for lead was 0.8 μg/L. Specifically, the study provided useful information for update of saltwater quality standards.